There are three major methods of wireless data transfer from downhole to surface (or vice versa) for oil and gas drilling in use today: mud pulse, electromagnetic and acoustic telemetry. In a typical acoustic telemetry drilling or production environment, acoustic waves are produced and travel predominantly along the metal wall of the tubing associated with the downhole section required to drill the well. The acoustic energy is usually detected by sensitive accelerometers, and sometimes by relatively less sensitive strain gauges. Care needs to be taken about the positioning and coupling of such devices to the tubing in order that the maximum signal energy can be extracted in order to optimize the detection system's signal to noise ratio (SNR). See U.S. Pat. Nos. 5,128,901 and 5,477,505 to Drumheller for a further discussion of this issue.
In the case of jointed pipe drilling, the surface detection system will be attached at some position below the traveling block (see FIG. 1), and despite such systems being relatively small (see, for example, U.S. Pat. No. 6,956,791 to Dopf et al.) can cause severe space constraint issues, particularly in the type of oil rigs that utilize top drive motors to turn the drillpipe. In the case of coiled tubing rigs, a similar space constraint arises (see FIG. 2) because there is normally very little space available to optimally attach the detection mechanism directly to the coiled tubing. Furthermore, the problem is compounded in the case of coiled tubing in that the coil—to which the accelerometer is beneficially attached—continually moves into or out of the well. The present invention addresses these constraints and seeks to provide novel means by which they may be overcome.